Sunday, February 28, 2010
Every year The Works, a children’s museum focusing on technology, held its annual Tech Fest. Though we have wanted to go in the past, we finally made it yesterday. Held from 9-5 at the Edina Community Center in suburban Minneapolis, the event attracted 1700 people last year and hoped to reach 2000 this year. This scientific event covers chemistry, astronomy, mechanical and electrical engineering.
We got there shortly after lunch and just in time for the second chemistry show. I have wondered what the Chemistry department does for its public outreach ever since seeing the Physics Department's show--Physics Force at Northrup Auditorium at the University Campus. Demonstrators—two women from the University of Minnesota Chemistry Department, began by dropping Mentos in a pop bottle so the carbon dioxide in the pop creates a geyser. The two women decomposed hydrogen peroxide by adding ground magnesium to it into an empty pop bottle. Water, a byproduct of the reaction is released as steam because the chemical reaction is so hot it vaporizes the liquid and partially melts the empty bottle. Physical properties are demonstrated by showing the glass threshold temperatures. Placing an onion into liquid nitrogen, normally -400 degrees Fahrenheit begins to boil and steam. The onion needs time to freeze through; when completely frozen, the young women take leather gloves and threw it on the floor. Though it crashed like a glass bottle—chemically it was still an onion. Some kids up front even complained of the onion smell. One of the women remarked, “Yes, it does smell a little. Chemistry usually doesn’t smell good.” The women explained that nitrogen can make anything freeze enough to create the glass effect—the point where any solid behaves like glass. Conversely, glass can be melted to behave like plastic. The demonstration also used balloons filled with hydrogen—like the Hindenburg, that they ignited. Adding different salts, they created different colored flames with different salts. Iron even created small sparks like fireworks.
We left the chemistry show just in time to see one of the shows of the Minnesota Planetarium. Though the planetarium awaits the construction of the new planetarium, it has a mobile show—though yesterday was shown on a two dimensional screen because of the sheer volume of participants. The show yesterday had many elements of the show at Mayo High School, it had lots of good information that was new and kept our interest. Showing us the largest canyon in the universe—Valles Marineris, the show had “brought us” to Mars. The canyon is 200 miles across, three miles deep and long enough to reach from New York to California. We also learned about light years; the light from the sun takes 12.5 minutes to reach earth and the moon. When reflected from the moon, it takes an additional 1.5 seconds to reach earth. We discussed dwarf planets; we have received only very bad pictures of Eres. In 2015 Voyageur shall pass by it and be able to send better pictures to us. Traveling at 30,000 miles per hour, it is twelve light hours away from earth. We learned so much!
After the two shows, my kids wanted to play the traffic game—Gridlock. The game can be played online by anyone who wants to. The station was run by the University of Minnesota-Institute of Technology. They also had a display explaining how the traffic control systems worked.
The kids also had a chance to examine chemical reactions by placing vinegar into a small, empty water bottle and baking soda into a balloon. The balloon was placed atop the bottle. When the soda mixed with the vinegar, carbon dioxide gas that was emitted inflated the balloon. After the balloon was tied off, the kids were able to examine the properties of the gas. Because carbon dioxide gas is heavier than the atmosphere, it falls to the ground rather than floating in the air.
There were many things we were not able to do because we ran out of time. However, there was much we could: we watched a robot by the Edina FIRST team robot, examined robotics projects made by University students, and constructed paper cars. We even brought home directions to make a drinking straw rocket. It was an extremely worthwhile visit to the cities—we had a great time and learned tons! The Works has monthly family Saturdays and several homeschool days throughout the year. We are definitely going to plan on making the trip for some of them.